5 U.S.C. § 5521

1. (1)“agency” means—
   1. (A)an Executive agency;
   2. (B)the judicial branch;
   3. (C)the Library of Congress;
   4. (D)the Government Publishing Office; and
   5. (E)the government of the District of Columbia;
2. (2)“employee” means an individual employed in or under an agency;
3. (3)“head of each agency” means—
   1. (A)the Director of the Administrative Office of the United States Courts with respect to the judicial branch; and
   2. (B)the Mayor of the District of Columbia with respect to the government of the District of Columbia; and
4. (4)“United States”, when used in a geographical sense, means the several States and the District of Columbia.